Water is the new carbon
However it is viewed, the movement of water forms a considerable component in the taming of the environment in our modern world. From the channelling of flows for water supply to the transport of waste, sewerage and rainwater away from habitable space, this important aspect of engineering is both taken for granted and ubiquitous in equal measure. The challenge has always been to understand a system that most users are unaware of. It could be argued that the current challenge of ‘climate change’ occurs on a continuum, from a developed world perspective, encapsulating issues such as social reform and the linkage of sanitation systems to public health issues in the nineteenth century, large infrastructure projects post both world wars in the twentieth century, environmental concerns in the 1970s and 1980s and continuing water conservation and resource management concerns up to the present. From the global perspective it can be noted that the rapid urbanisation in the last half of the twentieth century leaves more than half the world’s population without clean water supply and adequate sanitation provision (Gormley et al. 2013), arguably, at a different point in the continuum. While the nature of the challenge changes, the fundamental engineering questions remain very similar.